JP7192213B2 - Control device and control method - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a control device and control method, and more particularly to a control device and control method for a vehicle equipped with a manual transmission.

Generally, in a vehicle equipped with a manual transmission, engine power is transmitted to the manual transmission through a clutch device, and after being shifted at a predetermined gear ratio by the manual transmission, the propeller shaft and final gear are transmitted. (see, for example, Patent Documents 1 and 2).

JP 2016-35211 A JP 2017-57976 A

In a vehicle such as the one described above, when the transmission is operated to shift up, the engine speed corresponding to the gear stage after shifting up greatly deviates from the engine speed corresponding to the gear stage before shifting up. Then, when the clutch device is switched from disengaged to engaged, a large shift shock may occur. Such a shift shock poses a problem of deteriorating drivability.

An object of the technique of the present disclosure is to effectively improve drivability during an upshift.

A device of the present disclosure is a control device for a vehicle in which power of an engine is transmitted to a transmission via a clutch device, and includes rotation speed acquisition means for acquiring an actual rotation speed of the engine, and vehicle speed of the vehicle. a vehicle speed acquisition means for calculating an estimated engine speed after the shift-up based on at least the actual speed, the vehicle speed, and the gear ratio after the shift-up of the transmission; and control means for performing rotation speed reduction control to reduce the rotation speed of the engine when a difference between the estimated rotation speed and the actual rotation speed is equal to or greater than a predetermined threshold rotation speed.

Further, the rotation speed calculation means determines whether or not the transmission is operated to shift up based on at least the running state of the vehicle and/or the operating state of the engine, and determines if the shift up operation is performed. When determined, the estimated number of revolutions is calculated, and when the estimated number of revolutions is calculated, the control means determines whether or not a difference between the estimated number of revolutions and the actual number of revolutions is the threshold number of revolutions or more. is preferred.

Further, the apparatus further comprises connection/disconnection acquisition means capable of acquiring at least connection/disconnection of the clutch device, and the control means starts the rotational speed reduction control when the connection/disconnection of the clutch device is acquired by the connection/disconnection acquisition means. is preferred.

Further, it is preferable that the control means terminates the rotational speed reduction control when the engaged or half-clutch state of the clutch device is obtained by the disengagement/engagement obtaining means.

Further, the engine includes at least one of an intake throttle valve, a variable displacement supercharger, and a compression release brake device, and the control means controls the opening of the intake throttle valve as the rotational speed reduction control. is fully opened, the opening degree of the nozzle vane of the variable displacement supercharger is narrowed to the closed side, and the compression release brake device is operated.

Further, it is preferable that the threshold rotation speed is set based on a difference between the input and output rotation speeds of the clutch device that can cause shift shock when the transmission shifts up.

A method of the present disclosure is a method of controlling a vehicle in which power of an engine is transmitted to a transmission via a clutch device, in which an actual rotational speed of the engine and a vehicle speed of the vehicle are acquired, and at least the actual speed of the vehicle is acquired. An estimated rotation speed of the engine after the shift-up is calculated based on the rotation speed, the vehicle speed, and the gear ratio of the transmission after the shift-up, and the difference between the estimated rotation speed and the actual rotation speed is a predetermined value. It is characterized in that the rotation speed of the engine is reduced when the rotation speed is equal to or higher than a threshold rotation speed.

According to the technique of the present disclosure, it is possible to effectively improve drivability during upshifting.

1 is a schematic overall configuration diagram of a vehicle equipped with a control device according to an embodiment; FIG. 1 is a schematic overall configuration diagram of an engine mounted on a vehicle according to an embodiment; FIG. It is a functional block diagram showing a control device concerning this embodiment. FIG. 5 is a flowchart for explaining processing of rotational speed reduction control according to the present embodiment; (A) is a timing chart diagram schematically showing the transition of the engine rotation speed when the rotation speed reduction control according to the present embodiment is performed, and (B) is an engine when the rotation speed reduction control is not performed. It is a timing chart figure which shows transition of rotation speed typically.

A control device and a control method according to this embodiment will be described below with reference to the accompanying drawings. The same parts are given the same reference numerals, and their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[drive system]
FIG. 1 is a schematic overall configuration diagram of a vehicle 1 equipped with a control device according to this embodiment. An input shaft 82 of a manual transmission (hereinafter simply referred to as a transmission) 80 is connected to the crankshaft 11 of the engine 10 via a clutch device 40 so as to be connectable/disconnectable. The transmission 80 is connected to a shift operating device 89 provided in the driver's cabin via a link mechanism (not shown) or the like, and shifts are changed according to the operation of the shift operating device 89 .

An input shaft 82, an output shaft 83, a counter shaft 84, a plurality of transmission gear trains 85 provided on these shafts 82 to 84, a synchromesh mechanism (not shown), and the like are arranged in a transmission case 81 of the transmission 80. . Left and right driving wheels are connected to an output shaft 83 of the transmission 80 via a propeller shaft 87, a final gear (none of which is shown), left and right drive shafts, and the like.

The vehicle 1 also includes an engine rotation speed sensor (an example of rotation speed acquisition means) 90 that acquires the engine rotation speed Ne from the crankshaft 11, and a vehicle speed sensor that acquires the vehicle speed V of the vehicle 1 from the output shaft 83 or the propeller shaft 87. Various sensors such as (an example of vehicle speed acquisition means) 91 and a stroke sensor (an example of connection/disconnection acquisition means) 92 that acquires disengagement/engagement of the clutch device 40 are provided. Sensor values of these various sensors 90 to 92 are output to an electrically connected electronic control unit (hereinafter referred to as ECU) 100 .

The clutch device 40 is, for example, a dry single-plate clutch device, and an output side end of the crankshaft 11 and an input side end of the input shaft 82 are arranged in the clutch housing 41 . The clutch device 40 connects and disconnects the crankshaft 11 and the input shaft 82 according to the depression of the clutch pedal 67 by the driver. Specifically, when the driver depresses the clutch pedal 67, the crankshaft 11 and the input shaft 82 are switched from "connected" to "disconnected", and when the driver releases the clutch pedal 67, the crankshaft 11 and The input shaft 82 can be switched from "disconnected" to "connected".

[engine]
Next, based on FIG. 2, details of the engine 10 mounted on the vehicle of the present embodiment will be described. The engine 10 mainly includes a cylinder block CB and a cylinder head CH provided above the cylinder block CB. The cylinder block CB is provided with a cylinder C in which a piston P is accommodated so as to be able to reciprocate. Although only one cylinder is shown in FIG. 2, the engine 10 may be either a multi-cylinder engine or a single-cylinder engine.

The cylinder head CH is provided with an intake port 12 for introducing intake air into the cylinder C and an exhaust port 13 for leading out exhaust gas from the cylinder C. As shown in FIG. The intake port 12 is provided with an intake valve 14 that is opened and closed by a valve mechanism, and the exhaust port 13 is provided with an exhaust valve 15 that is opened and closed by a valve mechanism. Further, the cylinder head CH is provided with an injector 16 that directly injects fuel into the combustion chamber. Furthermore, a compression release brake device 30 is provided on the upper portion of the cylinder head CH.

An exhaust manifold 17 is attached to the exhaust side of the cylinder head CH, and an exhaust passage 18 is connected to the exhaust manifold 17 . The exhaust passage 18 is provided with a turbine 21 of a variable displacement supercharger 20, an exhaust purification device (not shown), and the like.

An intake manifold 24 is attached to the intake side of the cylinder head CH, and an intake passage 25 is connected to the intake manifold 24 . The intake passage 25 is provided with an air cleaner 26, a compressor 23 of the variable displacement supercharger 20, an intercooler 27, an intake throttle valve 28, and the like in this order from the upstream side. The opening and closing of the intake throttle valve 28 is controlled by operating an actuator (not shown) according to a command from the ECU 100 .

The variable displacement supercharger 20 includes a turbine 21 that is rotationally driven by exhaust gas, a nozzle vane 22 provided on the turbine 21, and a compressor 23 that is provided coaxially with the turbine 21 and pumps intake air. The opening and closing of the nozzle vanes 22 are controlled by the actuation of actuators (not shown) according to commands from the ECU 100 .

The EGR device 34 includes an EGR passage 35 that recirculates exhaust gas from the exhaust systems 17 and 18 of the engine 10 to the intake systems 24 and 25, an EGR cooler 36 that cools the EGR gas, and an EGR valve that adjusts the EGR rate (recirculation rate). 37.

The compression release brake device 30 increases the engine braking force by opening the exhaust valve 15 during the compression stroke and closing the exhaust valve 15 during the expansion stroke after the piston P has passed top dead center. . Specifically, in the compression release brake device 30, when an actuation signal is input from the ECU 100 to the electromagnetic solenoid 31 and the normal cam (not shown) is switched to the brake cam 32 by hydraulic pressure, the brake cam 32 causes the rocker arm 33 to move. By rocking, the exhaust valve 15 is forcibly opened during the compression stroke. As a result, the air in the cylinder C is discharged to the exhaust port 13 during the compression stroke, the air is not compressed in the cylinder C, and the kinetic energy of the piston P is lost. Next, the exhaust valve 15 is closed in the expansion stroke when the piston P has passed the top dead center. As a result, the inside of the cylinder C becomes negative pressure, and the generation of the force pushing down the piston P is suppressed, thereby effectively increasing the engine braking force.

[ECU]
FIG. 3 is a functional block diagram showing the control device according to this embodiment. The ECU 100 performs various controls of the engine 10 and the vehicle 1, and includes a known CPU, ROM, RAM, input ports, output ports, and the like. Further, the ECU 100 has an engine rotation speed calculation section (rotational speed calculation means) 110, a shift shock determination section (control means) 120, and a rotation speed decrease control section (control means) 130 as functional elements. ing. These functional elements are described as being included in the ECU 100, which is integrated hardware, but any part of them may be provided in separate hardware.

When it is assumed that the transmission 80 is shifted up from the current gear by the driver while the vehicle is running, the engine speed calculation unit 110 calculates the engine rotation speed corresponding to the gear (gear ratio) after the shift up. Estimate the number _{Ne_Cal} . Specifically, the engine speed calculation unit 110 calculates the current gear stage _Gn , the current vehicle speed _{V_Act} of the vehicle 1 acquired by the vehicle speed sensor 91, and the gear ratio corresponding to the gear stage _Gn+1 after the shift-up. , the engine speed _{Ne_Cal} after the shift up is calculated.

The current gear stage _Gn is the sensor value of the engine speed sensor 90 (transmission input speed) obtained when the clutch device 40 is engaged, and the sensor value of the vehicle speed sensor 91 (transmission output speed). should be determined based on Alternatively, if the vehicle 1 has a shift position sensor (not shown), the current gear stage _Gn may be determined from the sensor value of the shift position sensor. The engine speed _{Ne_Cal} after the shift-up may be calculated based on an arithmetic expression, map, or the like including the gear ratio of each gear stage, the vehicle speed, etc. stored in advance in the ECU 100 as input values. Assuming that the vehicle speed is substantially constant before and after the upshift, these calculation formulas and maps can be simplified.

Based on the current engine speed _{Ne_Act} acquired by the engine speed sensor 90 and the post-shift-up engine speed _{Ne_Cal} estimated by the engine speed calculation unit 110, the shift shock determination unit 120 It is determined whether or not shift shock can occur due to clutch engagement during upshifting. Specifically, the ECU 100 stores the input/output rotational speed difference of the clutch device 40 that may cause a shift shock as the determination threshold value _{Ne_Max} . The determination threshold value _{Ne_Max} may be appropriately set according to the setting of the gear ratio of each gear stage of the transmission 80, the specifications, and the like. Shift shock determination unit 120 determines that a shift shock may occur if a speed difference ΔNe between the post-shift-up engine speed _{Ne_Cal} and the current engine speed _{Ne_Act} is greater than or equal to a determination threshold value _{Ne_Max} .

When shift shock determination unit 120 determines that a shift shock may occur, rotation speed reduction control unit 130 performs rotation speed reduction control to reduce the engine speed. In the present embodiment, the engine speed reduction control is performed by increasing the pressure on the intake side more than the pressure on the exhaust side to increase the pumping loss of the engine 10 . Specifically, it is executed by any one of the following (1) to (3), or by selectively combining these (1) to (3).

(1) Control the opening of the intake throttle valve 28 to the opening side (preferably, fully open) to increase the intake flow rate. (2) The opening of the nozzle vane 22 of the variable displacement supercharger 20 is narrowed to increase the rotation speed of the turbine 21, thereby increasing the boost pressure (supercharging pressure). (3) The compression release brake device 30 is operated to increase the pumping loss of the engine 10 . It should be noted that the EGR valve 37 is preferably also controlled to be fully closed when the rotational speed reduction control is performed.

The engine speed reduction control is preferably started when the stroke sensor 92 acquires “disengagement” of the clutch device 40 . As a result, the engine speed can be rapidly reduced at the same time as the driver's shift operation (depression of the clutch pedal 67). Further, the rotational speed reduction control is preferably terminated when the stroke sensor 92 acquires the “engagement” of the clutch device 40 . That is, by continuously performing the rotational speed reduction control over the period from when the clutch device 40 is "disengaged" to "engaged", a high boost pressure state is maintained until immediately after the shift-up is completed. . As a result, it becomes possible to effectively improve the acceleration response after the upshift. Further, by prohibiting (non-executing) the rotation speed reduction control for increasing the intake air flow rate when the rotation speed difference ΔNe is smaller than the determination threshold value _{Ne_Max} , an excessive decrease in the exhaust gas temperature is suppressed. , and deterioration of exhaust emissions can be effectively prevented. Note that the rotational speed reduction control may be ended when the half-clutch state of the clutch device 40 is detected.

Next, processing of rotation speed reduction control according to the present embodiment will be described based on the flowchart of FIG. 4 .

In step S100, the running state of the vehicle 1 obtained from various sensor values such as the vehicle speed sensor 91, the operating state of the engine 10 obtained from the engine speed sensor 90, an accelerator opening sensor (not shown), etc., the stroke sensor 92 ( Alternatively, based on the operating state of the clutch pedal 67 (accelerator pedal released) acquired by an accelerator pedal sensor), the operating state of the brake pedal (brake pedal released) acquired by a brake pedal sensor (not shown), etc. It is determined whether or not the transmission 40 is in a state in which an upshift operation can be performed. If it is determined that the shift-up operation is possible (Yes), the process proceeds to step S110.

In step S110, the engine speed _{Ne_Cal} after the upshift is estimated based on the current gear _Gn , the current vehicle speed _{V_Act} of the vehicle 1 obtained by the vehicle speed sensor 91, and the gear _Gn+1 after the upshift. Calculate.

In step S120, it is determined whether or not the rotation speed difference ΔNe between the engine rotation speed _{Ne_Cal} after the shift-up and the current engine rotation speed _{Ne_Act} is equal to or greater than the determination threshold value _{Ne_Max} . If the rotational speed difference ΔNe is equal to or greater than the determination threshold value _{Ne_Max} (Yes), there is a high possibility that a shift shock may occur during an upshift, so the control proceeds to step S130.

In step S130, it is determined whether or not the driver has started a shift-up operation. That is, when the clutch device 40 is switched from "engagement" to "disengagement" based on the sensor value of the shift stroke sensor 92 (affirmative), it is determined that the shift up operation by the driver has started, and this control is executed. Proceed to step S140.

In step S140, engine speed reduction control is started to decrease the engine speed by increasing the pumping loss.

In step S150, based on the sensor value of the shift stroke sensor 92, it is determined whether or not the clutch device 40 has switched from "disengaged" to "engaged" (or in a half-clutch state). In the case of affirmative, the control proceeds to step S160, ends the rotational speed reduction control, and returns. On the other hand, if negative, the control returns to step S140. In other words, the rotation speed reduction control is continuously performed until the shift-up completion in which the clutch device 40 is "engaged".

The effects of the control device and the control method according to the present embodiment described in detail above will be described with reference to the timing chart shown in FIG. Note that FIG. 5A schematically shows the transition of the engine speed when the rotation speed reduction control is performed, and FIG. 5B shows the transition of the engine speed when the rotation speed reduction control is not performed. is schematically shown.

As shown in FIG. 5(B), when the rotation speed reduction control is not performed during the upshift, the engine rotation speed before the upshift (see time t1) and the engine rotation speed after the upshift (see time t2) Since there is a large discrepancy in the rotational speed difference between the two, the shift shock increases when the clutch is engaged, which may lead to deterioration of drivability.

On the other hand, as shown in FIG. 5(A), when the speed reduction control for increasing the pumping loss is performed at the same time as the start of the shift operation (time t1) at which the clutch is disengaged, the engine speed is rapidly reduced. become. That is, the engine speed difference between the engine speed before the shift-up (see time t1) and the engine speed after the shift-up (see time t2) is kept small (or the speed difference is set to substantially zero). ) becomes possible. As a result, it is possible to effectively suppress the occurrence of a shift shock when the clutch is engaged, and the drivability can be reliably improved.

Further, by continuously performing the rotational speed reduction control over the period from the time t1 when the clutch device 40 is disengaged to the time t2 when the clutch device 40 is engaged, a high boost pressure state is maintained until immediately after the completion of the shift up. As a result, it is possible to effectively improve the acceleration response after shifting up.

In addition, since the energy absorbed by the clutch device 40 due to the engagement of the clutch during upshifting is reduced, early wear of the clutch facing can be effectively suppressed.

It should be noted that the present disclosure is not limited to the above-described embodiments, and can be appropriately modified and implemented without departing from the gist of the present disclosure.

For example, in the above embodiment, the connection/disengagement of the clutch device 40 is determined by the stroke sensor 92. The determination may be made based on the gear ratio or the like. Further, the vehicle speed of the vehicle 1 has been described as being acquired by the vehicle speed sensor 91, but if the vehicle 1 has a wheel speed sensor (not shown), the wheel speed sensor may be used. Further, if the transmission 80 is provided with an input speed sensor, the engine speed may be replaced by a sensor value obtained by the input speed sensor while the clutch is engaged.

Reference Signs List 1 vehicle 10 engine 20 variable displacement supercharger 22 nozzle vane 28 intake throttle valve 30 compression release brake device 40 clutch device 80 transmission 90 engine speed sensor 91 vehicle speed sensor 92 stroke sensor 100 ECU
110 engine speed calculation unit 120 shift shock determination unit 130 speed reduction control unit

Claims (7)

A control device for a vehicle in which engine power is transmitted to a transmission via a clutch device,
a rotation speed obtaining means for obtaining the actual rotation speed of the engine;
vehicle speed acquisition means for acquiring the vehicle speed of the vehicle;
rotation speed calculation means for calculating an estimated rotation speed of the engine after the shift-up based on at least the actual rotation speed, the vehicle speed, and the gear ratio of the transmission after the shift-up;
When the difference between the estimated engine speed and the actual engine speed is equal to or greater than a predetermined threshold engine speed, engine speed reduction control is performed to decrease the engine engine speed and increase the intake air flow rate. A control device for a vehicle, comprising: control means that does not perform the rotational speed reduction control when the difference in numbers is smaller than the threshold rotational speed. The rotation speed calculation means determines whether or not the transmission is operated to shift up based on at least the running state of the vehicle and/or the operating state of the engine, and determines that the shift up operation is performed. calculating the estimated number of revolutions;
2. The vehicle control device according to claim 1, wherein when the estimated rotation speed is calculated, the control means determines whether or not a difference between the estimated rotation speed and the actual rotation speed is equal to or greater than the threshold rotation speed. further comprising connection/disconnection acquisition means capable of acquiring at least connection/disconnection of the clutch device;
The control device for a vehicle according to claim 1 or 2, wherein the control means starts the rotational speed reduction control when the disengagement of the clutch device is obtained by the disengagement/connection obtaining means. 4. The vehicle control device according to claim 3, wherein the control means terminates the rotational speed reduction control when the engaged or half-clutch state of the clutch device is acquired by the disengagement/engagement acquisition means. The engine comprises at least one of an intake throttle valve, a variable displacement supercharger, and a compression release brake device,
The control means performs, as the rotation speed reduction control, control to fully open the opening of the intake throttle valve, control to narrow the opening of the nozzle vane of the variable displacement supercharger to the closing side, and the compression release brake device. 5. The vehicle control device according to any one of claims 1 to 4, wherein at least one of the control for operating the 6. The vehicle according to any one of claims 1 to 5, wherein the threshold rotation speed is set based on a difference in input and output rotation speeds of the clutch device that can cause shift shock when the transmission shifts up. Control device. A vehicle control method in which engine power is transmitted to a transmission via a clutch device,
Obtaining the actual rotation speed of the engine and the vehicle speed of the vehicle, and estimating the engine after the shift-up based on at least the actual rotation speed, the vehicle speed, and the gear ratio of the transmission after the shift-up. A rotational speed is calculated, and if a rotational speed difference between the estimated rotational speed and the actual rotational speed is equal to or greater than a predetermined threshold rotational speed, rotational speed reduction control is performed to decrease the rotational speed of the engine and increase the intake flow rate. and not performing the rotation speed reduction control when the rotation speed difference is smaller than the threshold rotation speed.

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